Dr. Kate Shoulders says that the amount of power you use in your home will determine the size of the solar power energy system you’ll need. In this video she explains how to calculate the size of the system you’ll need.

Dr. Kate Shoulders of the University of Arkansas at Fayetteville said the first step to achieving energy independence is to assess how much energy your home is already using.
By making your home as energy efficient as possible on the front end, Shoulders said you can save a lot of money on the back end since the system you install won’t have to be as big.
“You need to consciously go throughout your house and look at how you’re using energy,” she said.
Here are some things to consider as you begin to make the move toward energy independence:

• Reduce “phantom power” loads. Even though the picture on your big screen television might be turned off, Shoulders said it’s still using energy because the TV is constantly searching for the remote. That’s a classic example of what Shoulders calls “phantom power,” also called “vampire power” or “standby power.” Phantom power refers to the power that electronic devices continue to use power even though they are turned off. The Lawrence Berkeley National Laboratory website state that almost any product with an external power supply, remote control, continuous display (including an LED), or charges batteries will draw power continuously, even when the device itself is turned off. The Discovery Channel once measured how much power a flat screen TV was using while it was turned off. The total came to about $60 per year! Shoulders said one of the best ways to reduce the phantom loads in your home is put devices on a power strip so the power to the device can be completely cut off .
• Utilize passive solar energy.  “Passive solar” refers to taking advantage of heat from the sun without using any devices. This can be achieved by simply having south-facing windows in your home. As the sun takes a lower trek across the sky during the winter months, that bright sunshine coming through a south-facing window can have the same effect on the inside of your home as it does on the inside of your car during the summer. Since its  not practical to change the orientation of your home, Shoulders said this option is usually for those who are building a home. She said she knows of some people who have placed solar panels over their south-facing windows to serve as a awning during the summer. Since the sun crosses the sky at a higher angle during the summer, the solar panel captures the sunlight and shades the window below to help cool the inside of the house.

• Insulation and weatherproofing. The “tighter” your house is, the  more energy efficient it will be. Shoulders said this means adding insulation where you can and sealing up any leaks you might find in your home.
• Be wise with the way you use energy. Simply consider ways to save energy during your regular routine. For example, don’t turn on the oven during the hottest part of the day only to have to crank up the air conditioner to keep the house cool. Instead of putting the clothes in the dryer every time, put them on a clothes line instead.
• Use solar-powered devices to help cut down on your power use. Shoulders said there are ways you can use solar power around your home without having to invest in a whole-house system. For example, she said installing a solar-powered fan in your attic can removed hot air and make your house to easier to cool. She said some people also use solar-powered water heaters to reduce their power bills.

Dr. Kate Shoulders, assistant professor in the Agriculture Education, Communications and Technology Department at the University of Arkansas at Fayetteville says not all forms of renewable energies are created equal.

One of Shoulders’ primary duties is to see which forms of  renewable energy (solar, wind and hydro) work best in Arkansas. To accomplish that goal, she started the Solar Energy Analysis Station at the UA farm in Fayetteville. Shoulders  uses the station to test practical ways renewable energy can be used in agriculture or a homestead.

Shoulders is quick to say that renewable energy is not necessarily the right fit for everyone, and some forms of renewable energy work better than others due to location, climate, economic feasiblity and other factors.

Wind is not a Good Option

While Arkansas is home to some companies that manufacture the gigantic wind turbines used for commercial wind power generation, Shoulders said wind is not a practical option in the Natural State.

There is a wind turbine set up at the analysis station in Fayetteville, but Shoulders said the primary reason it’s there is to show how “inefficient” wind-power is for Arkansas.

Shoulders said there are three primary reasons why wind power is not a very efficient option for renewable energy in Arkansas:

• First, turbine systems are designed primarily for constant West Coast winds that often blow close to the ground. In Arkansas, she said the turbine has to be elevated, which adds to the expense, and the wind is not very consistent here at all.
•  Second, she said turbine systems have several moving parts, which require more maintenance and expense, especially over the long term.
• Third, Shoulders said there are some unexpected regulations that can influence where you can put wind turbines. For example, she said twind turbines have proven to be very detrimental to the bat population. As a result, the Environmental Protection Agency has placed restrictions on using wind turbines in the flight patterns of bats.

“Wind is not as useful for Arkansas as solar,” Shoulders said.

Solar is Best Option in Arkansas

Shoulders said they are using solar energy in both “on grid” and “off grid” applications at the university farm.

“On grid” refers to using a form of renewable energy as a secondary source of power in addition to the electricity provided by a public utility. “Off grid” refers to using renewable energy as the sole source of power for a structure.

In on-grid applications at the Energy Analysis Station in Fayetteville, Shoulders said they have a 1 kilowatt solar generator to support power for a shop/classroom at the university farm. That on-grid system also helps power a micro-invertor that measures how much energy each cell in a solar panel is producing over any five-minute time frame. Shoulders said that data allows them and the public to see how well the solar panels are working under varying conditions.

To demonstration an off-grid application for solar power, Shoulders said they set up set up two water troughs in the middle of a pasture equipped with a water pump that  operates solely off a couple for solar panels connected to the pump. She noted that the system does not have a battery storage system – all the power to operate the water pump comes strictly from the solar panels themselves.

Shoulders said the intent of the solar-powered water trough demonstration is to show ranchers that they can deliver water to remote parts of their pasture without having to haul it. The pumps are using a 250-watt solar panel without any battery back-up. She said any time you can avoid having a battery back-up system, it makes the overall system much more cost efficient.

Shoulders said other practical off-grid applications for solar power without having to have a battery back-up system would include solar panels that could be used for portable charging stations for rechargeable tools at remote locations, solar water heaters, electronic gates and recreational uses for RVs, boats or camping.

She also noted that not all solar panels are created equal. While the price of the panels have come down in recent years, she said the power-generating silicon in some panels is superior to the silicon in others. Shoulders recommended checking out the efficiency of a panel before buying it.

Micro-Hydro System

Shoulders said the most efficient and affordable source of renewable energy is also the least available: micro-hydro.

She described the micro-hydro system as simply a miniature version of a hydro-electric power plant where a constant flow of water helps turn  a generator that produces electricity.

Since that stream flows constantly, Shoulders said the hydro generator can produce power around the clock regardless of the weather conditions. That makes it much more efficient than solar or wind power because both of those can be affected by the elements.

She said micro-hydro systems can be produce electricity with as little as 100 gallons of water going over a five-foot dropoff or five gallons of water going over a 100-foot dropoff.

While it is the most efficient and affordable system, Shoulders said not everyone has a stream that meets the flow requirements. However, if a person does have a flowing stream on their property, it would be the best option for a renewable energy source.